COUMAPHOS JMPR 1975
Explanation
This pesticide was previously evaluated in 1968 and 1972
(FAO/WHO, 1969, 1973). No further work or information concerning
residues in food and their evaluation was requested by the 1972
Meeting.
Attention is drawn to the possibility that in exceptional
circumstances the maximum residue limit of 0.5 mg/kg in milk (fat
basis) may be exceeded for a very short period (one day) and reach a
maximum of 2 mg/kg.
APPRAISAL
Trials in Sweden and Australia showed that coumaphos as an
emulsifiable concentrate controls mange in pigs (Sarcoptes Suis). In
the Netherlands in 1975 a similar formulation was found to be
effective against mange in cattle. These results stimulated the use of
coumaphos as a substitute for lindane or BHC mixed isomers for the
control of mange in cattle (Bayer AG, 1975). It is essential for
efficient mange control to treat all animals of a herd including
lactating cows. Because mange control treatments are not carried out
simultaneously in one area, it can be concluded that the milk from
treated herds will normally be diluted by a factor of four or more
with milk from untreated herds (see also Report of the 1971 Joint
Meeting, FAO/WHO, 1972). This results in residues below 0.5 mg/kg in
milk or milk products on a fat basis. On exceptional occasions, there
may be no dilution, and residues up to a maximum level of 1.6-2 mg/kg
in milk fat can be expected for a very short period (one day after
treatment). (See "Coumaphos", Table 5, FAO/WHO, 1973). This should be
taken into consideration when residues higher than 0.5 mg/kg in milk
fat are occasionally found in samples taken during food inspection.
FURTHER WORK OR INFORMATION
REQUIRED (by 30 June 1978)
See FAO/WHO, 1973a, pp. 44.
REFERENCES
Bayer AG. (1975) Veterinary Division, Submission for re-evaluation of
Coumaphos tolerance in milk (Unpublished letter from Bayer AG)
Kohn-Muelh, Drine/GW, 10.11.75.